The OPA1688 and OPA1689 are a family of SoundPlus™ 36-V, single-supply, low-noise operational amplifiers capable of operating on supplies ranging from 4.5 V (±2.25 V) to 36 V (±18 V). This latest addition of high-voltage audio operational amplifiers, in conjunction with the OPA16xx devices provide a family of bandwidth, noise, and power options to meet the needs of a wide variety of applications. The OPA168x are available in micropackages, and offer low offset, drift, and quiescent current. These devices also offer wide bandwidth, fast slew rate, and high output current drive capability. The dual and quad versions all have identical specifications for maximum design flexibility. Unlike most op amps that are specified at only one supply voltage, the OPA168x family is specified from 4.5 V to 36 V. Input signals beyond the supply rails do not cause phase reversal. The input can operate 100 mV below the negative rail and within 2 V of the top rail during normal operation. Note that these devices can operate with full rail-to-rail input 100 mV beyond the top rail, but with reduced performance within 2 V of the top rail.
“This is a headphone amplifier project for audio digital-to-analog converters (DACs) with differential voltage outputs. This circuit converts the differential voltage output of the DAC to a single-ended, ground-referenced signal and provides the additional current necessary for low-impedance headphones. Project …